The present invention relates to managing a set of software modules in a software runtime environment.
Computer systems commonly run application programs comprising a set of interdependent software modules provided in a software runtime environment. Such software modules may comprise dynamic dependencies with each other. Dynamic dependencies are managed by the software runtime environment such that the application program provided by the set of modules can continue to function despite appearance or disappearance of a relevant dependency. Dynamic software modules can thus have independent lifecycles; that is, they may be started, stopped, upgraded, replaced or removed regardless of the state of the other modules providing the relevant application program. For example, an administrator may change the lifecycle state of a given software module resulting in a change in dependencies. The dependencies are dynamically rearranged so as to enable the application program to continue to run, perhaps with reduced functionality.
Dynamic software runtime environments may allow the use of software modules comprising static dependencies, that is, dependencies on other software modules that are continuously required at runtime to enable the correct functioning of the relevant interdependent software modules. Such statically dependent software modules are commonly run within a wrapper arranged to adapt the statically dependent software module so as to enable it to operate within the dynamic software runtime environment. Such statically dependent software modules may be legacy software modules.
Exposing such statically dependent software modules to a dynamic software runtime environment can cause issues resulting from lifecycle state changes. For example, given two statically interdependent software modules, if one has its lifecycle state changed from running to stopped, this will cause a fault with the other and potentially a resulting issue with the application program that the modules contribute to. Furthermore, when dynamic software modules make use of static software modules, the dynamic software modules may effectively gain a static dependency. This results in the dynamic software modules not behaving dynamically as would otherwise be expected.